title: Elaboration, activity and stability of silica-based nitroaromatic sensors.
abstract: Functionalized silica-based thin films, modified with hydrophobic groups, were synthesized and used as sensors for nitroaromatic compound (NAC) specific detection. Their performance and behavior, in terms of stability, ageing and regeneration, have been fully characterized by combining chemical characterization techniques and electron microscopy. NAC was efficiently and specifically detected using these silica-based sensors, but showed a great degradation in the presence of humidity. Moreover, the sensor sensitivity seriously decreases with storage time. Methyl- and phenyl-functionalization helped to overcome this humidity sensitivity. Surface characterization enabled us to establish a direct correlation between the appearance, and increasing amount, of adsorbed carbonyl-containing species, and sensor efficiency. This contamination, appearing after only one month, was particularly important when sensors were stored in plastic containers. Rinsing with cyclohexane enables us to recover part of the sensor performance but does not yield a complete regeneration of the sensors. This work led us to the definition of optimized elaboration and storage conditions for nitroaromatic sensors.
authors.affiliation: UPMC Université Pierre et Marie Curie, UMR CNRS 7197, Laboratoire de Réactivité de Surface, LRC-CEA/UPMC/CNRS no 1, Paris, France.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Mercier
authors.forename: Franck
authors.initials: F
authors.lastname: Pereira
authors.forename: Christophe
authors.initials: C
authors.lastname: Méthivier
authors.forename: Pierre
authors.initials: P
authors.lastname: Montméat
authors.forename: Lionel
authors.initials: L
authors.lastname: Hairault
authors.forename: Claire-Marie
authors.initials: CM
authors.lastname: Pradier
mesh_terms: D009578:Nitrobenzenes / Q000032:analysis*; D010316:Particle Size; D012822:Silicon Dioxide / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D009578:Nitrobenzenes; D012822:Silicon Dioxide